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Carb Adjusting

I had a similar situation after a carb cleaning in terms of no ability to get it to idle at the correct rpm. It was so long ago that I can’t remember what I did to get it running at the necessary rpm for sync. Wish I had some ball park number of turns in for the balance screws to get them sort of bench synced. Keep playing with them.

The only reason to break the carbs down is to change out all the item #58 o-rings on the fuel rail. Other than that there is no cleaning benefit. These bikes/carbs are getting old and it sucks when the o rings leak after getting carbs cleaned.
 
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rouge, I'll toss this out there, most is probably wrong, but that hasn't stopped me from giving (ill)advice in the past.

The mixture screws on the FZ1 when turned out let more fuel in at idle and just off idle (up to about 1/8 throttle). You said your bike will idle with a small amount of choke (enrichening). But when you close the choke the engine dies. That to me means the engine isn't getting enough fuel.

I will try a lot of things before removing the carbs on this bike.

At this point I would turn the mixture screws out 4 turns and see what happens. Theoretically things should improve. It’s just fine tuning after that. I wouldn’t turn out much more than 5 turns as the screw may fall out.

I don’t have any (ill)advice on the idle speed adjustment not working. I looked at mine last night and the cable disappears between carb 2 and 3. Maybe if you looked down from above you could see what is going on. It was cold and I didn’t take the seat off or lift the fuel tank.

Hope this helps and feel free to correct me if I am wrong.

Jim
 
OP has to have issues somewhere else.
100% sure I'd be pulling the carbs and rechecking things before I tried 4 turns out on the A/F screws with stock jetting.
The Ivan's jet kits uses 4 or more turns out but that is due to the smaller ( 122.5) main jets with that kit in addition to the other modifications to the carb bodies.
 
Eff-Zed-1 said:
OP has to have issues somewhere else.
100% sure I'd be pulling the carbs and rechecking things before I tried 4 turns out on the A/F screws with stock jetting.
The Ivan's jet kits uses 4 or more turns out but that is due to the smaller ( 122.5) main jets with that kit in addition to the other modifications to the carb bodies.
Click to expand...
I agree. Sounds like something in the main jet circuit is plugged given that it dies with any throttle action.
 
Getting back to the carbs tomorrow as I've had to pull the transfer case out of my 98 Explorer! What a job! Half way there waiting on parts, so it's time for the bike!

I'm gonna separate the cabs & go through each one, as well as making sure every choke plunger (installed 1 new 1 on carb 4) is clean & the idle speed cable is adjusting all the carbs properly & make sure I installed everything correctly. Should have done this from the start. I'm getting pretty quick @ taking these carbs out now!! Not something I'm particularly proud of but hey!

Will keep you posted on what I find!
 
Pulled each carb apart from the rack, went through every jet, passage & set mixture screws @ 3 1/2 turns out. Checked the idle speed knob operation & it seems to be working properly. I backed it off of the throttle cable assembly & turned it back in so it just touches the lever. How many turns do you guys usually set that for a general bench setting? Not sure why it didn't change the idle speed before. Maybe it was bound up. I'll put a little cable lube in the cable just to make sure it's well lubed before reinstalling them.

Now to just make sure the sync levers are in the correct place when I put them back on the rack. Any advise there will help. Service manual doesn't show anything there but I took pics before disassembly so hope I can see those positions. For those that will wonder why I took them off the rack, I wanted to remove every choke plunger & accelerator pump to make sure there was no junk in the there & you can't get them all out without removing them from the rack. And those choke plungers!! Had to use needle nose pliers to loosen then as no socket or wrench will fit in there. Accelerator pumps on 1 & 2 had a lot of junk in there. 3 & 4 were clean. All the diaphragms were good. I also blew some carb cleaner & air into the ball socket to make sure that was clean too. Glad I did that. Could have been why it would die as soon as I tried to roll the throttle.

Anyway, I'll be finishing this today & see how it all turns out. Removal & install is easier than ever! Again, hope this is the last time for a while!!
 
killer5280 said:
Fingers crossed.
Click to expand...
All back together now. Was a tedious process getting those sync plates under the springs but I got em. Here’s a short run down. I highly advise taking postures as you break these carbs apart. There’s lot of little things to forget & miss but with progressive pics, you can backtrack & find your way.

Do them by the pair & have the air box side facing up- attach 1 & 2 1st so you can slide the long attaching bolt in. Back off the sync screws til the bottom of the screws are level with the plate that holds it. Slide the bolts into carb 1 & slip it to the far side of its mount hole & slide the 2 of the shorter spacers (there’s 4 short & 2 long. The long ones go between 2 & 3) onto each bolt. Slide carb 2 onto the bolts. Make sure the light wider spring is on the nut for the sync lever. That spring will sit inside the next carbs throttle plate rod end. As you get close, place the breather in between the carbs & align the fuel stubs with the next carb. Now lightly pull the 2 carbs together. The lever on the sync flap should touch the corresponding spring it matches with. Don’t pull the carbs together too hard since you need a little wiggle room to get the spring compressed. Once you’re there, get a small screwdriver into the 2nd ring of the srping & put the screwdriver against the accelerator body & pry the spring down to allow the sync lever to slide in above the spring. It’s quite the balancing act to make sure that you are aligned in the fuel rails, breather is staying in both carbs & you still have the spring compressed to allow the plates to come together. Now you can pull the carbs harder together to make sure all those things are stuck together.

Now do the same thing with 3 & 4.

Once you get 3 & 4 together, there’s the longer 2 spacers that go onto the bolts & 2 small spacers with a dimple on 1 side & a cup on the other. Each carb has a pillar on it that looks just like them but since there’s a little more room between 2 & 3, these spacers make up for that. You also have to make sure that you keep all the carbs in order as that makes the difference for these small pacers.

The center spring is the toughest. Make sure the center sync screw is backed out as this one needs the most leverage. Now you’re holding 4 carbs together, sliding 3 & 4 onto the bolts, checking the breather is staying put & the fuel rail is sliding into place. Same as before; pry the spring down (this is where I used the 90 degree pick to compress the spring). Once they’re joined, slide the bolts into carb 3, short spacer, carb 4 on, push the bolts all the way through to carb 4 until they stop & tighten those puppies down!!!! You can now pop a cold 1 & give yourself a big pat on the back!!

The 2 T fittings for the hoses that lead to the left lower crankcase are soft & you can now squeeze them in between 1-2 & 3-4.

Also make sure you put all the small cooling hoses & breather hose back in the bottom of the carbs & put all clamps in place. Once they’re back in it a bummer to get to them & get them on & clamps in place.

There’s a couple things I forgot on the 1st run but only took a minute to right my wrongs & get back on track.

Feel free to add or critique anything here. I looked everywhere for some tricks but found nothing. Good luck FZ1’ers!!
 
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Isleoman said:

This pic from Pat’s site shows the area where the paddles come together. Hope you’re done and not searching for any
Click to expand...

Isleoman said:

This pic from Pat’s site shows the area where the paddles come together. Hope you’re done and not searching for any lost balance springs.
Click to expand...
I saw this earlier. Wish I had someone here to take pics along the way as I broke them
down & back together. There’s a lot to this but once you get the 1st 2 carbs together, the 2nd set is easier & the 4 joined as well.

I’ve done this in a few bike. My Vmax was easier that this as the 2 sets oppose each other & the springs are much easier to get to.

Anyone ever done this & if so, did you bench set the sync screws & the idle speed screw? Would like to know a decent setting so Im not scrambling to keep the bike running.
 
Isleoman said:
[/URL]

This pic from Pat’s site shows the area where the paddles come together. Hope you’re done and not searching for any
Click to expand...

roguevfz1 said:
All back together now. Was a tedious process getting those sync plates under the springs but I got em. Here’s a short run down. I highly advise taking postures as you break these carbs apart. There’s lot of little things to forget & miss but with progressive pics, you can backtrack & find your way.

Do them by the pair & have the air box side facing up- attach 1 & 2 1st so you can slide the long attaching bolt in. Back off the sync screws til the bottom of the screws are level with the plate that holds it. Slide the bolts into carb 1 & slip it to the far side of its mount hole & slide the 2 of the shorter spacers (there’s 4 short & 2 long. The long ones go between 2 & 3) onto each bolt. Slide carb 2 onto the bolts. Make sure the light wider spring is on the nut for the sync lever. That spring will sit inside the next carbs throttle plate rod end. As you get close, place the breather in between the carbs & align the fuel stubs with the next carb. Now lightly pull the 2 carbs together. The lever on the sync flap should touch the corresponding spring it matches with. Don’t pull the carbs together too hard since you need a little wiggle room to get the spring compressed. Once you’re there, get a small screwdriver into the 2nd ring of the srping & put the screwdriver against the accelerator body & pry the spring down to allow the sync lever to slide in above the spring. It’s quite the balancing act to make sure that you are aligned in the fuel rails, breather is staying in both carbs & you still have the spring compressed to allow the plates to come together. Now you can pull the carbs harder together to make sure all those things are stuck together.

Now to the same thing with 3 & 4.

Once you get 3 & 4 together, there’s the longer 2 spacers that go onto the bolts & 2 small spacers with a dimple on 1 side & a cup on the other. Each carb has a pillar on it that looks just like them but since there’s a little more room between 2 & 3, these spacers make up for that. You also have to make sure that you keep all the carbs in order as that makes the difference for these small pacers.

The center spring is the toughest. Make sure the center sync screw is backed out as this one needs the most leverage. Now you’re holding 4 carbs together, sliding 3 & 4 onto the bolts, checking the breather is staying put & the fuel rail is sliding into place. Same as before; pry the spring down (this is where I used the 90 pick to compress the spring). Once they’re joined, slide the bolts into carb 3, short spacer, carb 4 on, push the bolts all the way through to carb 4 until they stop & tighten those puppies down!!!! You can now pop a cold 1 & give yourself a big pat on the back!!

The 2 T fittings for the hoses that lead to the left lower crankcase are soft & you can now squeeze them in between 1-2 & 3-4.

Also make sure you put all the small cooling hoses & breather hose back in the bottom of the carbs & put all clamps in place. Once they’re back in it a bummer to get them on & clamps in place.

There’s a couple things I forgot on the 1st run but only took a minute to right my wrongs & get back on track.

Feel free to add or critique anything here. I looked everywhere for some tricks but found nothing. Good luck FZ1’ers!!
Click to expand...
One last thing I saw as I was lubing the springs; make sure you loosen & tighten the sync screws so you can make sure the springs are seated properly.
 
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I did bench sinc the carb balancing screws by getting all the slides to the same point i.e. just to the point of opening.

I put all my carbs back together then struggled to get the springs into their spots. I used heavy thread like is used on canvas to tie the springs closed, then a pair of hemostats to place them. Once in place I cut the thread with an x-acto knife.

Hope you’ve got it ready to fire up.
 
Isleoman said:
I did bench sinc the carb balancing screws by getting all the slides to the same point i.e. just to the point of opening.

I put all my carbs back together then struggled to get the springs into their spots. I used heavy thread like is used on canvas to tie the springs closed, then a pair of hemostats to place them. Once in place I cut the thread with an x-acto knife.

Hope you’ve got it ready to fire up.
Click to expand...
I thought about removing & compressing the springs. Hemostats are a great idea! Don’t have those. Just thought it would be tougher than doing it the way I did. Will try your method next time.

I’ll set the sync screws by checking the throttle plate openings. Good call. Thanks.
 
Isleoman said:
I did bench sinc the carb balancing screws by getting all the slides to the same point i.e. just to the point of opening.
Click to expand...
I put a light behind the carbs to show the gap in the throttle plates & adjust the screws for no opening of any throttle plate but carb 2 won’t close completely while all the others do. I was thinking of making sure that plate was properly seated & thought about removing the 2 shift to plate screws & see if it needs to be centered, but I think they’ve never been removed & are still peened over. Am I on the right track?
 
Yes you're going about it correctly. I’m like you and wouldn’t try to remove those plate screws.


There are two tiny holes in the bottom of the carb opening that the gold plates sweep over. Can you get all four plates to be aligned over the inner hole (so partially open) as opposed to all four plates closed or does #2 carb plate still seem off?

I have a set of spare carbs on my bench and I can do both. All four fully closed or all four over the holes roughly aligned in the same position

Once carbs are in the bike the pressure gauges will be your guide and they’ll all likely be different.
 
Isleoman said:
Yes you're going about it correctly. I’m like you and wouldn’t try to remove those plate screws.


There are two tiny holes in the bottom of the carb opening that the gold plates sweep over. Can you get all four plates to be aligned over the inner hole (so partially open) as opposed to all four plates closed or does #2 carb plate still seem off?

I have a set of spare carbs on my bench and I can do both. All four fully closed or all four over the holes roughly aligned in the same position

Once carbs are in the bike the pressure gauges will be your guide and they’ll all likely be different.
Click to expand...
After a little more fiddling I got them pretty much close to closed. #3 was still a little open but I thought like you said here; get em close & put the sticks on them.

All back together with fuel pump cycled til it stopped she started right up with 1/2 choke but wouldn’t idle without me on the throttle a bit. Turned the idle speed screw in 2x, still wouldn’t idle but it was closer. Another turn & a half & she idled @ 1k. Opened the throttle a little to see if it would accelerate & she do that well! Had to close the choke to 1/4 so she’d come back to idle again, & did. Sticks were all crazy; 1 the lowest; 2 the highest by a lot; 3 &4 were just over what 1 was. But she idled, ran & responded to throttle! Big step forward!!

Have to get me transfer case for my Explorer done quickly as that & my 06 M5 need to get back on the road. Have a friends loaner for now but will be getting back on the FZ hopefully by weekend & get her sync’d & move on to road ready!!

Fun times!! Thanks for all the input, IOM!!!
 
Good news!

It would be interesting to see where the plates are now after using the gauges. I’ll understand if you’ve had enough carb pulling. It does get faster with each time you do it.
 
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